Improvement in sewing-machines



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SEWING MAGHINE. No. 22,240. Patented Dec. 7, 1858.

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No. 22,240. Patented Dec. '7 1858.

UNITED STATES PATENT OFFICE.

SAMUEL F. PRATT, OF ROXBURY, MASSACHUSETTS.

IMPROVEMENT IN SEWINNG MACHINES.

Specification forming part of Letters Patent No. 22,240, dated December7, 1858.

To all whom it may concern:

Be it known that I, SAMUEL F. PRATT, o Roxbury, in the county of Norfolkand State of Massachusetts, have invented a new and useful or ImprovedSewing-Machine; andI do hereby declare that the same is fully describedand represented in the following specification and theaceompanyingdrawings,.of which- Figure 1 denotes a top view of it as itappears with the cloth rest or plates removed from the table. Figs. 2and 3 are side elevations. Fig. 4 is a front end elevation. Fig. is avertical and transverse section, taken through the cam-shaft. Fig. 6 isa top view of the expanding-hook, its slider, and closingspring. Fig. 7is a top view, and Fig. .8 a side view, of the thread-carrier. Fig. 9 isa longitudinal and vertical section, taken through the needle.

The said machine is intended'to accomplish the sewing of cloth or othermaterial by the interlooping of two threads, one being carried by aneye-pointed needle-that is, a needle having its thread-eye close to itspoint-and the other by a thread carrier or adjuster, with which a hookor expansion-hook is employed to effect the formation of loops and theirpassage through those of the needle, the nature of the principal part ofmy invention consisting in the combination of the thread carrieroradjuster and the hook when applied and used with a needle operating inmanner substantially as described. The needle penetrates the cloth andforms its loops therein, whereas the threadadjuster and the expansionhook do not pierce the cloth, but operate so to form loops out side ofit.

The nature of the invention further consists in a peculiarthread-carrier or a hook or barb and a slot, or its equivalent,operating in conjunction or combination to effect the proper seizure ofthe lower thread and its disposal with respect to the loop of theneedle, in order that such lower thread may be seized by the mechanismfor drawing it through the needleloop. v

1n the drawings, A represents the table or frame of the machine; B, theneedle, supported by a carrier, 0, which turns on a fulcrum, I), and hasreciprocating motion imparted to it by the rotary motion of a crank-pin,E, working in a slot, F, of the lower arm of said needle-carrier O. Thepin E is carried by a crank,

Arranged in the frame A in manner as shown in the drawings vis thethread-carrier M. (Exhibited in end view in Fig. 4:, and also in otherrespects in Figs. 7, 8, and 9.) When in operation, it has longitudinalmotion and intervals of rest imparted to it, the same being obtained bymeans of a slotted cam, N, which extends downward from it, as shown inFig. 2, and receives a pin or stud,O, projecting from the lower arm ofthe needle-carrier O. In the front end of the carrier M there is avertical slot, (1, for the reception of the thread 1), leading from thelower spool, c, and underneath'a hook or barb, (1, formed on the inneredge of the body of the thread-carrier, as shown in the drawings. Thisbarb stands in such relation to the slot to and the thread carrierbetween the two (which is bowed and curved in such manner that that partof the thread which is between the slot and the barb becomes, as itwere, the chord of an are) as to enable the hook P (to be hereinafterdescribed) to seize the thread constituting such chord. This hook isrepresented at P as attached to a horizontal slide, R, from which .astud, 0, projects and enters the grooved cam K, such cam being for thepurpose of producing the necessary intermittent longitudinal movementsof the said slide-bar. The hook 1? is constructed in two parts, fg, asshown in Fig. 6, one of whichviz., -is fastened to the slide-bar, so asto be immovable relatively thereto. The other part of the .hookviz.,

fprojects from a lever, 71-, having a fulcrum, t, carried by the sliderR. The outer end of the said lever carries a projection, k, whichextends downward and against the periphery of the cam or wiper L, theobject of the said cam or wiper being to cause the lever to so turn onits fulcrum as to move the part faway from the part 9 of the hook whensuch may be necessary, a spring, Z, attached to the slide bar R, andacting against aprojection, k, serving to move the lever in the oppositedirection, so as to close the two parts of the hook.

Fig. 10 is a side view of the cam or wiper L, while Fig. 11 is a sideview of the cam K, as developed on a plane surface.

By means of the slotted cam N and the up-.

ward and downward movements of the stud O,

the thread-carrier is moved backward, then rest for another period. Theforward move ment of the thread-carrier causes its thread to be seizedby the barb d in order that the thread extending between the said barband the upper part of the slit a may be'properly presented to theexpanding hook I after the thread-carrier has been retracted, such portion of the thread being carried back of the needle.

In the operation of the machine the needle having a thread, at,proceeding from a spool, 0, arranged as shown in the drawings, is firstmade to descend through the cloth and next to rise a little, in order tospread its loop. This having taken place, the expanding hook I? is nextmoved toward the needle and passes aside of the same through its loopand against the thread of the thread-carrier M, the inclined front endof the hook striking the thread and elevating it as the hook continuesto move forward, which it will do until the barb passes beyond thethread, so as to seize the same.

The next operation of the machine is the retraction of the expandinghook I during which the thread of the thread-carrier will be seized bythe hook and drawn in the form of a loop through the loop of the needle,the part f of the hook being moved in the meantime,

away from the part 9-, so as to spread or open the loop on them in aproper manner to enable the needle to pass through such loop during thenext descent of the said needle, preparatory to which the cloth may besupposed to have been so fed along by the feeding apparatus as toincline the loop sufficiently for the needle to enter it. After theneedle has entered the loop of the lower thread the hook I? shouldadvance a little in order to disengage from it the loop held by it.Next, the hook is again retracted and closed preparatory to anotherforward movement into another loop of the needle. Vhenever the hook isbeing drawn backward the thread-carrier should be in the act of beingmoved forward, so as to enable the thread to be drawn off its barb cl-Fur thermore, the thread-carrier should have such lateral movements aswill cause it to clear the needle and to fetch the thread of the carrieras close up to the needle as possible preparatory to such threadbeingseized by the hook I. In Fig. 7 is represented a small cam, 0, onthe inner edge of the thread-carrier. Such The drawings show part of thefeeding apparatus, but as such constitutes no portion of my presentinvention it is not necessary to enter into any further description ofthe same. The spool 0, carrying the thread, has the lower end of itsshaft or spindle spivoted on a step or washer, if, supported by t-heneedle carrier. The upper end is pivoted against a teiisionspring, at,whose rear end is fastened to the needle-carrier. A regulating-screw,4),

extends through the tension-spring and screws into the needle-carrier.Vith such an ar rangement or applicationof the tension-spring to thespindle of the spool, the spring not only performs the function of abearing to the spindle, or a support for its bearing, but is renderedcapable of being sprung away there from, so as to permit the spindle tobe detached from its bearings or supports without the necessity ofdisturbing or revolving the tension-adjusting screw. 4

In most, if not in all other kinds of tension apparatus, the device forregulating the tension has to be moved preparatory to the (lc-,

tachment of the spool, and as a matter of course the regulation of thetension is disturbed, and subsequently it has to be obtained anew; butwith my said application and arrangement the spindle may be removedwithout any disturbance or turning of the tension-screw.

Having thus described my invention, I claim-- 1. For inter-looping twothreads in order to sew cloth or other material by means of aneye-pointed needle, or its equivalent, the combination of a threadcarrier or adjuster, M, and a hook, P, so acting together and with theeye-pointed needle, or its equivalent, as not only to cause the threadof the carrier to be laid or presented in rear of the needle in a propermanner to be seized by the hook, but to cause the hook to pass throughthe loop of the needle, seize the thread of the carrier, and next recedeand draw the said thread in the form of a loop through the loop of theneedle and properly present it for the needle to pass through it duringits next downward movement after the cloth may have been fed along thelength of a stitch.

2. The thread-carrier M, constructed with the slit a, or its equivalent,and barb d, operating, in the manner described, to present the lowerthreadto the reciprocating looper-hook, which will draw it through theloop formed in the needle-thread.

In testimony whereof I have hereunto setmy signature. I

S. F. PRATT.

- lVitnesses: v

.R. H. EDDY, F. P. HALE,

